Frost indicator for refrigerators



July 7, 1953 R. J. CARBARY FROST INDICATOR FOR REFRIGERATORS Filed Dec. 21 1950 2 Sheets-Sheet l Figa l n f, /ff

His Attorne/ y Inventor Richard J. Cafbar R. J. CARBARY FROST INDICATOR FOR REFRIGERATORS F-s .7: 39 S July 7, 1953 Filed Dec. 21, 195o Inventor Richard d. Cafbafy.

His Attown yatentecl'l july 7,

FROST INDICATOR FOR REFRIGERATORS.

Richard J. Carbary, Erie, Pa., assignor to General Electric Company, a corporation of New York Application December 21, 1950, Serial No. 201,972

2o claim'.` (omis- 114) My invention relates to refrigerators and more particularly to frost indicators for refrigerator evaporators.

` In many household refrigeratorsr the food storage compartment is cooled by an evaporator whose surface is exposed to the air in the compartment. Consequently moisture condenses from the air on the substantially cooler surface of the evaporator and collects thereon as frost. In order to maintain a satisfactory efficiency of the refrigerating apparatus it is necessary to remove this frost from time to time, and hence it is desirable to call the users attention to the thickness of frost collected thereon and particularly to call to his attention the presence on theevaporator of frostof a predetermined maximum thickness. In connection with horizontal, or full width, evaporators which extend substantially the full width of the food storage compartment and are covered by the evaporator door, it is difcult for the user to determine the amount of frost collected on the evaporator and hence easy for him toV overlook the necessity for defrosting. Moreover, with this type of evaporator the thickest blanket of frost usually collects on the rear wall of the evaporator where it is completely concealed from the users view. By my invention I have provided arrangements which clearly indicate to the user the thickness of frost collected on the evaporator and more particularly indicate the thickness of frost on the otherwise concealed rear wall of the evaporator. Moreover, the indicators are positioned so as to minimize the danger that the need for defrosting may be overlooked by the user.

It is an object of my invention to provide an improved arrangement for indicating t-he thickness of frost on a refrigerator evaporator.

It is another object of myV invention to provide an improved arrangement for indicating the thickness of frost on a refrigerator evaporator each time the evaporator door is opened.

It is another object Aof my invention to provide an improved frost indicating arrangement particularly adapted for full width evaporators and including an element engaging the frost each provide a slidable member positioned between the side wall of the evaporator and the side wall of the liner forming the food storage compartment. rThis member includes a laterally extending element adapted to engage the frost on the rear wall of the evaporator, and the member is biased forwardly by a spring so as to bring this element into engagement with the frost. The slidable member is engaged by the evaporator door in its closed position to move the element away from the frost against the bias of the spring. The slidable member engages a pivoted or rotatable indicating element positioned at the forward portion of the `food storage compartment, and the slidable member is connected to the indicating element so that the amount of movementof the slidable member, as determined by the thickness of frost yunder rear wall of the evaporator, determines the position of the indicating element. Suitable indicia are employed for indicating the thickness of frost or at least for indicating when an abnormal amount of frost has collected on the evaporator.

For a better understanding of my invention reference may be had to the accompanying drawings in which Fig. 1 is a view of a portion of a refrigerator cabinet illustrating an embodiment of my invention; Fig. 2 is a side elevation .View showing details of one form of my invention; Fig. 3 is `a plan View of the form of invention shown in Fig. 2; Fig. 4 is an enlarged View of a portion of the mechanism illustrating details of operation;l Fig. 5 is a front view, partly broken away, of the indicating mechanism; Fig. 6is a side elevation view of a modif-led form of my invention; Fig. 7 is a plan View of the form of invention shown in Fig. 6; Fig. 8 is a front sectional elevation view of a portion of the indicating mechanism; Fig. 9 is an elevation View of a portion of the front of the refrigerator illustrating the indicating arrangement; and Fig. 10 is a side elevation View of another modified form of time the evaporator door is opened to indicate the thickness of frost.

Further objects and advantages of my invention will become apparent as the following description proceeds and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

In carrying out the objects of my invention I my invention.

Referring to the form of invention illustrated in Figs. l through 5, there is shown a refrigerator l including an inner liner 2 deninga food storage compartment 3. The food storage compartment is cooled -by an evaporator 4i which is of the horizontal, or full width, type extending substantially the full width of the food storage compartment 3. The access opening of the evapora- Ytor il is closed by a door 5 having a handle 6 thereon. The door 5 is hinged for movement abouta horizontal axis, and is biased to its closed hinges are old and detailed showing and description thereof are not believed necessary.

During normal operation, the evaporator 4 being exposed to the air in the food storage compartment 3, moisture from the air condenses on the walls of the evaporator and collects thereon in the form of frost. This frost may eventually reach a thickness sunicient to reduce materially the effectiveness of the evaporator. The frost built up is particularly large along the rear wall 8 of the evaporator. In order to indicate to the user the thickness of frost collected on the evaporator and particularly the relatively1 large thickness of frost which may collect on the concealed rear wall 8, an indicating arrangement Vincluding a slidable member 9 is provided. The slidable member 9 is disposed in the space between the side wall I of the evaporator and the side wall I I of the liner 2. The slidable member 9 includes a laterally extending portion or frost-engagement element I2 adapted to engage the frost on the rear wall 8 of the evaporator. The frostengaging element includes a nat plate I2a so as to provide a large area of contact with the frost, thereby minimizing penetrationv of the frost by the frost engaging element.

For slidablymounting the slidable member 9 on the side wall II of the liner two supports or support members i3 and I4 are provided. The front support or bracket I3 is adjustably mounted on the side wall I! at the front portion thereof by screws I5 and nuts Ia or other suitable fastening devices passing through elongated slots I6 in the bracket. The rear support or stud id is mounted at the rear portion-of the side wall II by a screw I'I and nut I3 or other suitable fastening devices. The bracket I3 includes a return bent section I9 having an opening therein for slidably receiving the forward end of this slidable member S. A strip I9@ of suitable plastic material is mounted on the section I9 to provide a bearing surface for the slidable member 9. The rear portion of the slidable member 9 includes an elongated slot 2t within which the stud I4 is received for slidably supporting the rear end of the slidable member' 9. biased forwardly in a direction in which the frost-engaging laterally extending element I2 moves toward the frost on the rear wall 8 of the evaporator by a spring 2 I. One end of the spring engages the bracket I3 and the other end engages the slidable member 9.

Tov cover the space between the side wall Ie of the evaporator and the side wall Ii of the liner a ller strip 22 of plastic or other suitable material is employed. This filler strip is mounted on the anged front surface 23 of the evaporator by screws (not shown) or other suitable fastening devices, and a gasket 24 for the evaporator door 5 overlaps the inner edge of the filler strip 22. The filler strip has an opening 25 provided therein through which the front end of the slidable member 9 projects. The evaporator door 5, when in its closed position against Athe gasket 24, moves the slidable member S rearwardly to the position shown in Figs. 2 and 3 and the solid lines in Fig. e wherein the frost-engaging element I2 is spaced from the frost 26 shown on the rear wall 8 of the evaporator. The evaporator door 5 is biased to its closed position by a spring or other suitable biasing device suiiiciently strong to overcome the relatively weak biasing force of the spring 2l.

It can be seen that each time the evaporator door 5 is opened the slidable member 9 is moved The slidable member 9 is by the biasing spring 2I from the rearward position illustrated in Figs. 2 and 3 and the solid lines in Fig. 4 to a forward position in which the frost-engaging element I2 engages the frost 26 on the rear wall 8 of the evaporator. The amount of this forward movement obviously varies dependent upon the thickness of the frost 26V on the rear wall of the evaporator, and is illustrated for one frost condition by the dotted lines in Fig. 4. This variation in the' forward movement of the slidable member e' depending 'on the frost thickness on the evaporator isutilized to move an indicating element visible from the front of the vrefrigerator-to indicate the thickness of frost and ultimately the need for defrosting. in the form of invention illustrated in Figs. l through 5 themslidable member S is formed of generally channel cross section and includes a front face 27 projecting beyond the iiller strip 22 and directly visible to the user when the evaporator door is in its open position. An opening 23 is provided in the upper portion of this front face 2l to provide-a view of a portion 29 of an indicating element 3Il. The portion 29 constitutes a generally fiat element somewhat wider than the opening 28. The indicating element 3d is pivotally mounted on the slidable member 9 by pin 3 I, so that the position of the portion 2Q of this indieating element varies as the indicating element pivots about the pin 3i. In'order to eifect such pivoting of the indicating element 3G coincident with the sliding movement of the slidable member e the bracket or support 'i3 is formed to provide an elongated opening orslot 32 which is inclined with respect to the line of movement of the slidable member 9. The pivot indicating element Se is provided'atits rear end with a lateraliy extending pin 33 which projects into the inclined slot 32.

It can be seen that movement of the pin 33 along the inclined slot 32 will effect a pivoting of the indicating element 3d, the amount of this pivoting being dependent upon the extent of the movement of the pin 33 relative to the slot 32,. This relative movement is utilized to indicate the frost thickness on the evaporator. Thus when the evaporator 5 is in its closed position and the slidable element e has therefore been moved rearwardly to the solid line position' shown in Fig. Li the pin 33 occupies the position substantiallyv at the right hand end of the inclined slot 32 and the pivoted rindicating element 3e is held in a position wherein the portion 29 is immediately behind the opening 2k3 in the front face 2? of the slidable member 2S. When the evaporator door is opened by the user for access to the contents of the evaporator the biasing force exerted by the door on the slidable member a is removed and the slidable member 9 is moved forwardly by the biasing spring 2l until this forward motion is stopped by engagement of the frost-:engaging element I2 with thefrost 2e on the rear wall 8 of the evaporator. As the 'slidable member 9 moves forwardly the pin 33 moves with the slidable member 9 and rides upwardly in the inclined slot 32 effect: ing a 'counterclockwise pivoting 'of the indicating element 3i). This VpivotingV effects a downward movement of the portion 29 of the indicating ele? ment, the amount of downward movement being dependent on the forward movement oi' the slidable member 9 and hence upon the thickness of the frost 26.

The condition when there is no frost present on the rear wall 8 of the evaporator is shown by the dotted lines in Fig. 4. In this situation the frost-engaging element vI2 has moved forwardly into direct engagement with the rear wall 8 of the evaporator and the motion of the slidable member v9 is sufficient to leflect Vmovement of thepin 33 to the dotted line position indicated, moving the'indicating element Y30 "inva counterclockwise direction to an extent suicientto move the portion 29 of the indicating element completely below the opening 28 so that none of the portion 29 of -the indicating element is visible VVthrough this opening 28. As varying thicknesses 30 is Apivoted on the slidable member 9 and the inclined slot 32 is provided in the support or bracket I3, itwill be apparent that, if desired, the parts could be reversed so that the indicating element is pivoted on the bracket I3 and the inclined slot 32 is provided in the slidable member 9.

The front face 21 ofthe slidablemember 9 may be marked with suitable indicia to indicate directly, by relation of the indicia to the top edge of the portion29, the thicknessY of frostY on the evaporator. Alternatively such indicia may be omitted, reliance being had merely upon the progressively vgreater amount ofthe portion 29 visible to the opening to indicate to the user the increasingjamount of frost and ultimately the need for defrosting. For greater noticeability the front face of the portion 29 may be painted in some conspicuous color, such as red, which will assistin` calling'the frost condition to the users attention. Forfurther accenting the noticeability a U-shaped member 34 may be secured to the interior of the slidable member 9 with a face 35 thereof spaced slightly rearwardly from the front face 21 of the slidable member 9. This face 35 may then be painted in some contrasting color, such as green. Hence when there is substantially no frost on the evaporator a green background will appear through the openingr 28 and, as the frost thickness builds up and the red portion 29 gradually becomes visible through the opening 28, the green background will be progressively reduced and the red background progressively increased.

In Figs. 6 through 9 inclusive there is shown a modified form of my invention which operates on the same general principle asthat previously described but differs details of construction and inthe use of a different form of indicating element. The same numerals have been used to designate corresponding parts in Figs, 1 through and Figs. 6 through 9. As in a form previously described the evaporator 4 is disposed in the top portion of thekfood storage compartment 3 defined by the liner 2 and this evaporator extends substantially the full Width of the food storage compartment. In the space between the side wall I6 of the evaporator and side wall I I of the liner a slidable member 36 is disposed. Two supports or support members 31 and 38 are mounted on the liner at the front and rear portions respectively of the side wall II. The front support 31 is mounted on the liner by a screw 39iand nut.40.

or other suitable fastening device. The rear sup'- port 38 is secured to the liner by screws 4I or` Aother suitable fastening devices. The rear support 38 is formed of plastic or other similar material and includes two horizontal passages, one of which is shown at 42,1for slidably supporting the rods 43 and -44 of the rslidable member .36. The slidable member 35 includes a laterally extending portion or element 45 adapted to engage the frost 26 collected on the rear. wall 8. of the evaporator. The element 45 includes a covering piece of rubber tubing 45a to provide a relatively wide frost engaging surface, minimizing penef tration of the frost by the element 45 and also minimizing adhesion to the frost. The front end of the slidable member 33 extends through an opening d6 in a filler strip i1 of plastic or other similarmaterial which closes the space between the side walls IU and II of the evaporator and liner respectively. The end of the slidable member 36 is bent at right angles in front of the iiller strip 41 tok present a relatively flat surface i8 which is engaged by the door 5 in its closed rear wall of the evaporator.

member .35 may, if desired, be supported by the l front support or-bracket 31.

As in a form previously described, the slidable member is resiliently biased forwardly toward a-.positionwher'ein the element 45 is brought into engagement with the frost 25 on the rear wall of the evaporator. This bias is provided by a spring y i3 mounted on the slidable member 36.' One end 55 of the spring engages the rear support 38 and the other end 5I engages a spaced vertical section 52 of the wire or rod from which the slidable member 36 is formed. Each time the evaporator door 5 is moved to its open position the slidable member 36 is biased forwardly by the spring 59. When the evaporator door 5 is closed the bias of the spring 49 is overcome and the slidable member 3S is moved to the rearward position illustrated.

It can be seen that the amount of forward movement of the slidable member 36 upon the opening of the door is governed by the thickness of the layer of frost 26 on the rear Wall of the evaporator. This is utilized by my invention for providing a visible indication of the amount ofv frost collected thereon. To provide such indication a wheel 53 is rotatably mounted on the front support or bracket 31.` The wheel 53 is supported by a spacer 54 mounted on the screw 39, a washer 55 disposed between the head of the screw 39 and a section 56 of the spacer retaining the wheelys in its assembled position. The wheel 53 is mounted directly behind an opening 51 `formed in the filler strip 41, a portion of the wheel 53 being clearly visible through the opening 51. In order to effect rotation of the wheel 53 so as toV present different sections thereof to view through the opening V51 under different frost conditions, the indicating element 3E is provided with a depending pin 58 which extends through an opening or slot 59 in the rim 60 of the wheel 53. As the slidable member 36 moves lforwardly when the evaporator door 5 is opened, the wheel 53 is rotated in a counterclookwise direction as viewed in Fig. 6 by engagement of the pin 58 with the opening sa in the wheei, the pin and slot @en nection. allowingY relative vertical movement of 7 the member 36 and the engaged portion of the rim of the wheel '53.

When the evaporator door e is closed the wheel 53 occupies the position illustrated in Figs. 6-9, and the slidable member te is disposed in a rearward position wherein the element 45 is spaced from the frost 2E. When the evaporator door is opened the wheel is moved in a counterclockwise direction, as viewed in Fig. 6. The amount of rotation of the wheel and its ultimate position are determined by the amount of forward movement of the slidable member 36 and this forward movement, in turn, is determined by the thickness of the frost on the rear Wall S of the evaporator. I-lence the final position of the wheel 5.2 indicates the thickness of frost. This indication may be eiiected by providing suitable legends or indicia on the rim Sil of the wheel 53 and upon the nller strip si adjacent the opening 5i. For example, in Fig. 9. there is shown a speciiic form ci indicia in which an arrow Si is provided on the wheel and the ller strip 4l and the area beside the opening 5i is inscribed with the legend Def., for Defrost, and Normalf If the arrow ti occupies a position in the area covered by the legend Normal the frost layer on the evaporator is I" a thickness below that at which defrosting is essential. Conversely, if the arrow occupies a position beside the legend Def., this indicates that the thickness of the frost layer 2S is above a predetermined maximum and the evaporator should be defrosted promptly for eiilcient operation. Alternatively, as in the form previously described, a section of the rim (i9 of the wheel 53 could be painted in some conspicous color such as red so that the visiblity of this red section or a substantial portion thereof through the opening l indicates the need for defrosting. Further adjacent sections or the entire remainder oi the rim Gil may be painted in a contrasting color, such as green, so that, when substantially no frost is present on the rear wall S of the evaporator, an entirely green background is visible through the opening 5i and, as the frost layer 2e progressively builds up, an increasing red area is visible through the opening 5l.

In Fig. lil there is shown another modiiied form of my invention which is substantially the same as that illustrated in Figs. 5 through 9 inclusive except for small structural 4changes in the iront support and in the iront portion of the slidable member, and the specic manner of engagement between the slidable member and the wheel. The same numerals have been used to designate corresponding parts in Fig. 10 and in the previous figures. A slidiable member 36 is positioned between the evaporator and the side wall of the liner 2 as in the forms previously described. A iront support 62 is secured to the liner 2 and a wheel 53 is mounted on this support B2 and on the liner in the same manner as the wheel 53 in the form illustrated in Figs. 6 through 9 inclusive. The wheel t3 is disposed behind the opening 5i and the iller strip lll', vso that a section of the rim of the wheel is visible through the opening 5l. In order to effect rotation of the wheel 53' coincident with sliding movement of the member S', a slot or opening 6,3 is provided in the side wall or tace ofthe wheel 53Y and a portion 5d of the slidable member its extends into the slot 63 for engagement with the wheel 53. The slot 63 is elongated to provide for relative vertical movement between the engaged portion of the Wheel 3e'. The movement of the wheel to indicate the thickness of the frost layer on the rear wall of the evaporator is the same as in the form illustrated in Figs. G through 9 and similar legends or coloring maybe employed on the rim of the wheel end on the filler strip il to indicate the frost conditions. In order to provide for engagement of the slidable member 35' by the evaponator door 5 in its closed position the slidable member 3 includes a rod E55 which extends through an opening in the ller strip M andV includes a portion 65 extending at right angles for providing a relatively iiat area for contact with the door 5. rPhe manner of operation of the form of invention illustrated in Fig. 10 is the same as that described in detail in connection with Figs. 6 through 9 inclusive.

While I have shown and described vspecific embodiments of my invention I do not desire my invention to be limited to the particular constructions shown and described and I intend, by the appended claims, to cover all modications within the spirit and scope of my invention.'`

What l' claim as new and desire to secure by Letters Patent of the United States is:

l. A refrigerator comprising a liner defining a food storage compartment, an evaporator upon which frost collects disposed in said compartment, a member slidably mounted adjacent said evaporator and including an element movable toward and away from said evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on said evaporator whereby the amount of movement of said member is determined by the thickness of said frost, inea-ns for biasing said member for movement of said element toward said evaporator, an oscillatory indicating element having a directly visible portion, and means connecting said indicating element and said member for ei'lecting oscillatory movement of said indicating element in acf cordance with said movement of said member whereby said visible portion of said indicating element indicates at least the general range of thickness of frost on said evaporator.

2. A refrigerator comprising a liner dening a food storage compartment, said liner including a side wall and a rear wall, an evaporator upon which frost colle-cts disposed in said compartment, said evaporator including a side wall spaced from the side wall of said liner and a rear wall spaced from the rear wall of said liner, a member slidably mounted in the space between said side walls of said evaporator and said liner, said member including a laterally extending portion movable toward and away from said rear wall of said evaporator, the movement of said laterally extending portion toward said rear wall of said evaporator being intercepted by the frost co1- lected on said rear wall of said evaporator whereby the amount of movement of said member is determined by the thickness of said frost, means for biasing said member forwardly for movement of said portion toward said evaporator, an oscillatory indicating element having a directly visible portion, means connecting said indicating element and said member for effecting oscillatory movement of said indicating element in accordance with said movement of said member whereby said visible portion of said indicating element indicates at least the general range of thickness of frost on said evaporator, and means for normally maintaining said laterally extending portion spaced from said frost against the bias of said f biasing means.

3. A .refrigerator including a liner defining a food storage compartmenaan evaporator upon which frost collects disposed in said. compartment, a member slidably mounted adjacent said 'evaporator and including an element movable toward and'away from said evaporator, movement of said element toward said evaporator being intercepted by the frost collected on the evaporator whereby the amount of movement of said member is determined by the thickness of said frost, means for biasing said member for y Y movement of said element toward said evaporator, an oscillatory indicating element having a directly visible portion, means connecting said ,indicating element and said member for effectanda door for said evaporator, said door engaging said member.A for maintainingA "said rstnamed element spaced from Vsaid frost against the bias of said biasing means; i

4. A refrigerator having a liner dening a food Vstorage compartment, an evaporator upon which frost collects disposed lin said compartment, a member slidably mounted adjacent said evaporator and including an element movable toward and away from said evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on the evaporator whereby the amount of movement of said member is determined by the thickness of said frost, a spring forbiasing said memberv for movement of said element toward said evaporator, an oscillatory indicating element having adirectly visible portion, means connecting said indicating element and said member for effecting oscillatory movement of said indicating element in accordance with said movement of said member whereby said visible portion of said indicating element indicates at least the general range of thickness of frost on said evaporator, a, door for said evaporator, said door in its closed position engaging said lmember for maintaining said first-named element spaced from said frost, and means for biasing said door to its closed position with a force sufficient to overcomethe biasof said spring.

5. A refrigerator comprisingaliner dening a food storage compartment, said liner including a side wall-and a rear wall, an evaporator upon which frost collects disposedY in said compartment,- said evaporator including a side wall spaced from the side wall of said liner and a rear wall spaced vfrom the rear wall of .said liner'a first support secured to the front portion of said side wall oi. said liner, a second supportl secured to they rear portion of said side wall of said liner, a member slidably mounted on said supports and disposed inv the space between said side wallsY of said evaporator and said liner, said member including a laterally extending portion movable toward and away from the rear wall of said evaporator, the -movement of saidV laterally extending portion toward said rear wall of said evaporator being intercepted by the frost collected on the evaproator whereby the amount of movement of said member v'is determined by the thickness of said frost, means for biasing said member forwardly for movement oi' said laterally extending portion toward said A rear wall of said evaporator, an oscillatory indieating element having a directly visible portion,

1D of said indicating element in accordance with said'movement of said member wherebyv said visible portion of said' indicating element indicates at least the general range of thickness of frost on said evaporator, and means for normally maintaining said laterally extending portion spaced fromy said frost against the bias of said biasing means. Y 6. A refrigerator comprising a liner dening a food storage compartment, said liner including a sidewall and a rear wall, an evaporator upon which frost collects disposed in saidcompartment, said evaporator, extending substantially the full width` of 4said compartment and including a side wall spaced frornthe side wall of said linerr andA a rea-r wall spacedfrom the rear wall ofsaid.

liner, a ,member slidably mounted in the space between said sidewalls oisaiol evaporatorand said liner, said member including a laterally ex'- tending -portionmovable toward and away from said rear wall of saidpevap'orator, themovement 0i said laterally extending portion toward said rear wall of said evaporator being intercepted by the-frost on said evaporator whereby the movement of said member .isfdetermined by the thickness of said frost, vmeans'for'biasing said member `forwardly for movement-of said laterally extend- Apositionyengaging said' kmember ,-folf normally maintainingsaid laterally, extending DOItiOn spaced from said frost against thebiasof said biasingmeans.` w

7. Arefrigerator comprising a liner dening a food storage compartment, said liner including a side wall and a rear wall, lan evaporator upon which -.frost collects disposed in said compartment, said evaporator including a side wall spaced from the side vwall of said liner and a rear wall spaced-from the lrearsyvall of, said liner, a bracket VVsecured to the front .portionlofv said side wall: of said liner, said rbrackethaving an opening therein,V

a stud mounted ontherearportionfof said side wall .of 'said linen/ra' member movably mountedon said "bracketV andsaid stud and disposed in the spacebetween said side walls o1 said evaporator andsaidliner, said member extending through said opening in said bracket and including an elongated slotrfor receiving said stud, said member including a laterallyf'extendingfportion movable toward and away from said rear wall of said evaporator, the4 movement of said laterally extending portion toward said rear wall of said evaporator being intercepted by the frost collected on said evaporator whereby the amount of movement of -said'membergis determined by the thick'-` nessof said frost, means for biasing said member forwardly for movement of said laterally extending portion toward said rear wall of said evaporator, an oscillatory indicating element having a directly visible portion, andmeans connecting said indicating element and'said member for eiecting oscillatoryr movement ofsaid indicating element in accordance with said movement of said member whereby said visible portion of said indicating element indicates at least the general range oi thickness of frost on said evaporator.

8. A refrigerator comprising a liner defining a food storage compartment, an evaporator upon which frost collects disposed in said compartment, a stationary support member, a second member movably mounted on said support member and including an element movable toward and away from said evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on the evaporator whereby the amount of movement of said member is determined by the thickness of said frost, means for biasing said secondmember for movement of 'said element toward said evaporator, and means' for normally maintaining said element spaced from said frost against the bias of said biasing means, one of said members including a slot inclined with respect to the line of move` ment of said second member, the other of said members including a pivoted oscillatory arm having a pin extending into said slot whereby said movement of said second member causes a pivoting of said arm and determines the position of said arm, said arm further including a directly visible portion for directly indicating the thickness of frost on said evaporator.

9. A refrigerator comprising a liner defining a food storage compartment, an evaporator upon which frost collects disposed in said compartment, a stationary support member, a second member movably mounted on said support member and including an element movable toward and away from said evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on said evaporator whereby the amount of movement of said member is determined by the thickness of said frost, means for biasing said second member for movement of said element toward said evaporator, and means for normally maintaining said element spaced from said frost against the bias of said biasing means, said support member including a slot inclined with respect to the line of movement of said second member, said second member including a pivoted arm having a pin eX- tending into said slot whereby said movement of said second member causes a pivoting of said arm and determines the position of said arm, said arm further including a directly visible portion for indicating at least the general range of thickness of frost on said evaporator.

10. A refrigerator comprising a liner defining a food storage compartment, an evaporator upon which frost collects disposed in said compartment, a stationary support member, a member movably mounted on said Support member and including an element movable toward and away from said evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on said evaporator whereby the amount of movement of said member is determined by the thickness of said frost, means for biasing said second member for movement of said element toward said evaporator, means for normally maintaining said element spaced from said frost against the bias of said biasing means, said second member including a front face having an opening therein, an oscillatory indicating element, and means connecting said indicating element and said second member for eifecting oscillatory movement of said indicating element in accordance with said movement of said second member, said indicating element including a portionA movably disposed `behind said. face and adapted to have varying amounts exposed through said opening depending on the thickness of frost on said evaporator.

1i. A refrigerator comprising a liner defining a food storage compartment, an evaporator upon which frost collects disposed in said compartment, a stationary support member, a second member movably mounted on said support member .and including an element movable toward and away from said evaporator, the movement of element toward said evaporator being intercepted by the frost collected on the evaporator whereby the amount of movement of member is determined by the thickness of said frost, means for biasing said second member for movement of `said element toward said evaporator, means for normally maintaining said element spaced from said frost against the bias of said biasing means, said second member including a front facehaving an opening therein, a pivoted arm, means connecting said pivoted arm and said second member for effecting rotational movement of said pivoted arm in accordance with said movement or" second member, said arm including a portion movably disposed behind said face and adapted to have varying amounts exposed through said opening depending on the thickness of frost on said evaporator.

l2. A refrigerator comprising a liner dening a food storage compartment, an evaporator upon which frost collects disposed in said compartment, a stationary support member, a second member movably mounted on said support member and including an element movable tov-fard and away from said evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on said evaporator whereby the amount of movement of said second member is determined by the thickness of said frost, a door for said evaporator, said door in its closed position engaging said second member for maintaining said element spaced from said frost, a spring engaging said second member and said support member for biasing said second member for movement of said element toward said evaporator, said second member including a front face having an opening therein, a pivoted arm, means connecting said pivoted arm and said second member for effecting rotational movement of said arm in accordance with said movement of said second member, said arm including a portion movably disposed behind said face and adapted to have varying amounts exposed through said opening depending on the thickness of frost on said evaporator.

13. A refrigerator comprising a liner dening a food storage compartment, an evaporator .upon which frost collects disposed in said compartment, a stationary Support member, a second member movably mounted on said support member and including an element movable toward and away from vsaid evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on said evaporator whereby the amount of movement of said second member is determined by the thickness of said frost, means for biasing said second member for movement of said element toward said evaporator, vand means for normally maintaining said elet ent spaced from said frost against the bias of Naid biasing means, said second member including a front face having an opening therein, said support member including a slot inlined with respect to the line of movement of said second member, said yment of said second member causes a pivoting of said arm. said arm including a portion disposed behind said front face and adapted tohavevarying amounts, exposed through said opening depending on the thickness of frost on said evaporator. Y

amasarl 14.` A refrigerator comprising a liner dei-ming a food storage compartment, an evaporator upon whichfrost collects disposed in said compartment, a stationary support member,v a second member movably mounted on said support member and including'an element movable toward and away from said evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on said evaporator whereby the amount of movement of said member is determinedby the-thickness `of said frost, means for biasing said second member for movement of said'element toward said evaporator, and means for normally maintaining said element spaced from saidorost against the" bias of said biasing means, -saidv second member including a rfront face having an opening therein, said second member ,including a lsecond face spaced rearwardly from said front face and directly visible through saidfopening, said support member including slotrinclined with respect to the line 1of movementY l face being of one color and said lportion of said pivoted arm being of a contrasting color.

15. A refrigerator comprising a liner defining food storage compartment, an evaporator upon which frost collects disposed in said compartment, a member movably mounted adjacent said evaporator and including an element movable toward yand away from said evaporator, the movement of said element toward said evaporator being interceptedby the frost collected on said evaporator whereby the amount of movement of said member is determined by the thickness of said frost, means for biasing said member for movement of said element towardsaid` evaporator, a wheel-rotatably mounted at the forward portion of said compartment, means connecting said wheel and said member for effectingmovement of saidwheel in accordance with said movement oi said member whereby the position of said wheel indicates at least the general range of thickness of frost on said evaporator, and means for normally maintaining saidY element spaced from said` frost against the bias of said biasing means.

16. A refrigerator comprising a liner dening a food storage compartment, said liner including a side wall and a rear wall, anevaporator upon which frost collects disposedin said compartment, said evaporator extending substantially the full width of said storage compartment and ncluding a side wall spaced from the side wall of said liner and a rear wall spaced from therear wall of said liner, a member movably mounted adjacent said evaporator and including a laterally extending portion movable toward and away from said rear wall of said evaporator, the movev ment of said laterally extending portion toward said evaporator being intercepted-by the frost collected on said'evaporator whereby the amount of movement of said member is determined by the thickness of Said frost, means for biasing said member forwardly for movement of said laterally extending portion toward said evaporator, a, filler strip between said side wall ,of said evaporator and said side wall of said liner, saidller strip having an opening therein, av wheel rotatably mounted on saidliner behind said opening in said filler strip, a portion of said wheel being exposed' through said opening, means connecting said wheel and said member for effecting rotational movement of saidwheel in accordance with said movement of said member whereby the portion of said wheel exposed through said opening indicates at least the'generalrange of thick-A ness oi frost collected on said evaporator,'and

means for normally maintaining said laterally 'extending portion of said member spaced. frein said frost against the bias of said biasing means.v

17. A refrigerator comprising a liner defining a food storage compartment, an evaporator on which frost collects disposed in said compart-` ment, a member movably mounted adjacent said evaporator including an element movable toward and away from said evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on said evaporator whereby thefamount of movement of said member is determined by the thickness of said-frost, means for biasing said member for movement of said element toward said evaporator, a wheel rotatably mounted at the forward portion oisaid compartment, said wheel including a rim having an opening therein, said member including a pin extending into said opening vfor effecting rotational movement of said wheel in accordance with said movement of said member whereby thel position of said wheel indicates at least the general range of thickness of frost collected on said evaporator, and means for normally maintaining said element spaced from said frost against the bias of said biasing means.

18. A refrigerator comprising a liner defining a food storage compartment, said liner including a side wall and a rear wall, an evaporator upon which frost collects disposed in saidcompartment, said evaporator including a side wall spaced from the side wall of said liner and a rear wall spaced from the rear wall of said liner,

a first support secured to the front portionof said side wall of said liner,v a second support secured i to the rear portion of said side wall of said liner, a member movably mounted on said supports and disposed in the space between said side walls of said evaporator and said liner, said member including a laterally extending portion movable toward and away from said v rear wall of said evaporator, thev movement of said portion'toward said rear wall of said evaporator being inter-v cepted by the frost collected on said rear wall of said evaporator whereby the amount of movement of said member is determined byithe thickness ofsaid frost, a spring engaging said member and one of said supports for biasing said member forwardly for movement of said laterally extending portion toward said rear wall of said evaporator, a wheel mounted on said first support, said member including means for engaging said wheel for effecting rotational movement oi saidl wheel in accordance with said movement of said member whereby the position of said wheel indicateg at least the general range of thickness Vof the frost collected on the rear wall of said evapo- 1.5v Y rator, and means' for normally' maintai laterally extending portion spaced .i frost against the bias oiv said biasing 19. A refrigeratorA comprising a liner defining a food storage compartment, said liner including a side wall and a rear wall, an evaporator upon which frost collects disposed in said compartment, said evaporator extending substantially the full width of said storage compartment and including a side wall spaced from the side .vall of said liner and a rear wall spaced from the rear wall of said liner, a member movably disposed in the space between said side walls of said evaporator and said liner, said member including a laterally extending portion movable toward and away from said rear wall of said evaporator, the movement of said laterally extending portion toward said rear wall of said evaporator being intercepted by the frost collected on said rear Wall of said evaporator whereby the amount of movement of said member is determined by the thickness of said frost, means for biasing said member forwardly for movement of said laterally extending portion toward said rear wall of said evaporator, a iler strip between said side Wall of said evaporator and said side Wall of said liner, said ller strip having a first opening therein, said member including a second portion extending through said opening, a door for said evaporator, said door in its closed position engaging said second portion of said member for normally maintaining said laterally extending portion spaced from said frost against the bias of said biasing means, said ller strip having a second opening therein, and a wheel rotatably mounted behind said ller strip and having a portion exposed to view through said. opening, said member including means for engaging said wheel to rotate said wheel in accordance with said said movementl of said member whereby the amount of rotation of said Wheel is determined by the thickness of frost collected on said rear wall of said evaporator, said wheel and said filler strip adjacent said opening including indicia for indicating at least the general range of thickness of frost on the rear wall of said evaporator, 20. A refrigerator comprising a liner defining a food storage compartment, an evaporator on which frost collects disposed in said compartment, a member movably mounted adjacent said evaporator and including an element movable toward and away from said evaporator, the movement of said element toward said evaporator being intercepted by the frost collected on said evaporator whereby the amount of movement of said member is determined by the thickness of said frost, means for biasing said member for movement of said element toward said evaporator, a wheel rotatably mounted at the forward portion of said compartment, said Wheel having an elongated opening in the side thereof, said member including a pin extending into said elongated opening for rotating said wheel in accordance with said movement of said member whereby the position of said Wheel indicates at least the general range of thickness of frost collected on said evaporator, and means for normally maintaining said element spaced from said rost against thebias of said biasing means. RICHARD J. CARBARY.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,371,395 Rast Mar. 15', 1921 2,007,407 Schweitzer July 9, 1935 2,112,261 Ba-ckstrom Mar. 29, 1938 

